Step 1: Parts
Because the cabinet is tall and has wooden shelves, installing a single light at the top would only illuminate the top shelf. Installing five standard cabinet lights, while possible, would be expensive and involve more wiring than I wanted to do. After considerable research I settled on LED lights in ribbon form from HitLights, but there are several suppliers.
Advantages of LED ribbon lighting are: 1) Low voltage (more or less impossible to get shocked or burn down the house), 2) low wattage (cheap to run), 3) low heat (won’t melt your stuff), 4) flexible (literally, it’s a ribbon, super bendy), 5) self-adhesive (3M double stick tape), 6) good quality light (available in day light, warm white, and primary colors), and 7) never burns out. Let me repeat, Never Burns Out.
1 – spool (16.4’) LED ribbon (HitLight or other)
1 – 12v power supply
Soldering iron and solder
Blue painter's tape
Isopropyl alcohol and paper towels
The LED spool costs about $12, and the power supply costs $11, so the total cost is under $25, remarkably cheap.
Step 2: The LED Ribbon
The second photo shows the basic unit of the LED ribbon light. Each unit has 3 LEDs and a current limiting resister. You can cut the ribbon on the indicated line and it will still work. Each unit is just a tad under 2” (exactly 6.5cm). More than one ribbon, or cut segments, can be joined by soldering the tabs at the cut marks (so long as you pay attention to the polarity). Every 10th unit the solder tabs are pre-tinned, so if possible you want to cut there. If you are not comfortable with soldering, they do sell solderless connector, but I didn’t try those.
Step 3: Installation
I decided to install the LED ribbon on the door of my cabinet. For even lighting, I wanted it on both sides of the door, so that was going to involve cutting and soldering. The ribbon is so low profile (about 1/16th of an inch) that I had no problems with it impacting shelves or hardware, the door closed just fine with the ribbon attached.
First I ran the ribbon down the hinge side of the door, using lots of blue tape, with the power connector at the bottom. Then I cut it off at the top on the nearest cut line. I applied power to make sure it still worked, and opened and closed the door to make sure everything was free and clear.
The remaining length of LED ribbon was more than long enough to do the other side of the door. As I mentioned earlier, one end of the uncut ribbon has a power connect, but the other end has two wires pre-soldered on. I ran the other half of the LED ribbon down the other side of the door (more blue tape) with the pre-soldered wires at the bottom, since I intended to use those wires to power the second ribbon.
Again I cut it off at the top at the nearest cut mark. Just to be clear, the waste part of the LED ribbon, the part I cut off and didn’t use, came from the middle of the ribbon. In my project I used the front end with the power connector, and the back end with the pre-soldered wires.
Step 4: Testing
Again I opened and closed the door to insure there weren’t any problems.
Step 5: Stick It Down
Sticking the LED ribbon down isn’t hard, but you want to keep it under very slight tension as you go so you don’t get wrinkles or waves in it. Gravity helps with this, so I started peeling off the backing from the 3M adhesive at the top, and worked my way down, removing blue tape as I went. Firm it down with your fingers at the end.
Step 6: Drilling
Step 7: Soldering
Notice the little plastic clip that the power line is feeding though. That’s a strain relief and it came with the HitLights, nice touch from them.
The other end of the two hookup wires go to the LED ribbon on opposite side of the door. In the photo the solder joints are already covered by heat-shrink tubing, my personal favorite way to insulate wire connections. Electrical tape would also be just fine here.
Step 8: Conclusion
This kind of lighting could easily be used for shadow boxes or other artwork, under cabinet lighting in a kitchen, or any place that’s restricted or otherwise hard to light conventionally. It is also inexpensive and easy to work with.
As a final plug for LED, I’ll show what my KILL A WATT meter indicates this lighting project is drawing... just 17 watts. About the same as an old fashioned night light.